Referee 101

Can someone inform me what the referee rules are in parenting. There has been alot of crying lately. I really need some advice. My boys are starting to fight and over toys. Karson thinks its ok to try to take toys and things from Kaden. Kaden also does not like Karson having his toys so he grabs them from Karson. Because they both have been guilty of taking from the other when I do not see what happened I do not know who to give the toys back to.

DO YOU:

1. Give it to the child who owns it?
2. Do you take your oldests word for it?
3. My youngest does not have a full vocabulary. Then when they can both talk what do you do?
4. Do you take it away from both of them since they did not share?
5. Do you encourage your kids to share all their toys with each other with no ownership?

I have started the say your sorry and give the other a hug thing but it seems like forced love.

Just asking. I need some advice, comments, and ideas. I am new to this mother of 2 thing.